The DCC for the Pilot Studies of Candidate Therapies project will carry out the following tasks: assist the Steering Committee in its evaluation and finalization of Pilot Studies. For each approved trial, the DCC will work with the SC to develop a Manual of Operations and data collection forms, a customized data management system with a Web-based data entry interface and a secure Oracle 10gR2 database and establish a web site for each Pilot Study. Web sites will include all study documentation and a link to that study's secure data entry system train clinical center and central facilities personnel on data collectio, data entry, and data discrepancy resolution and the requirements for each approved pilot study assist the Clinical Centers in a) participant recruitment, retention, and adherence to treatment arm and b) site adherence to the study protocols and to IRB and regulatory requirements maintain a high quality database of each pilot study's data and provide periodic reports to the Steering Committee, the Data Safety and Monitoring Board , and the NIH Project Office on each Pilot Study, including progress on recruitment, protocol compliance, retention, subject safety, and data quality work with the Collaborative Study Group (CSG) to performing data analyses for abstracts, presentations and peer-reviewed publications manage the logistics, administration, and project-wide regulatory requirements for the Pilot Studies establish cores such as central labs, drug distribution centers, and reading centers as required by the study orchestrate the transfer of biologic samples to the NIDDK Bio-specimen and Genetic Repositories and ensure archiving of each Pilot Study's data in the NIDDK Data repository The DCC also proposes a Pilot Study. Should the DCC protocol be selected and finalized by the Steering Committee, the DCC would coordinate a 36-month pilot clinical trial of allopurinol vs placebo, with 12 months of randomization and a minimum of 24 months follow up per patient. With 200 patients (100 in each arm), this Pilot Study would be larger than all previous published trials of allopurinol in CKD. This Pilot Study would enable the CSG to evaluate challenges to drug distribution, recruitment, retention, follow up data collection (including laboratory data), data quality, participant compliance and clinical center adherence to protocol requirements. The Pilot Study would be powered to detect a 2-year change in a reasonable biomarker (eGFR estimated by MDRD-4). This Pilot Study would provide additional scientific justification for a full scale trial of allopurinol. It would also demonstrate the challenges of conducting such a trial, allowing these challenges to be addressed before the full scale study begins and thus enabling a scientifically sound full scale study with a hard endpoint outcome to be implemented efficiently.